style: adjust folder icon animation durations

Changed animation durations for folder icon scaling and positioning
to create smoother visual transitions. The scale animation duration
increased from 400ms to 600ms, while the x and y position animations
increased from 400ms to 800ms. This provides a more deliberate and
polished feel when folder icons animate into their grid positions,
enhancing the overall user experience with smoother motion.

style: 调整文件夹图标动画持续时间

修改了文件夹图标缩放和定位的动画持续时间，以创建更平滑的视觉过渡。缩放动
画持续时间从400毫秒增加到600毫秒，而x和y位置动画从400毫秒增加到800毫秒。
这使得文件夹图标在动画进入网格位置时具有更从容和精致的感觉，通过更流畅的
运动提升了整体用户体验。

Author: mhduiy

qml/IconItemDelegate.qml

@@ -208,21 +208,21 @@ Control {
                                         property: "scale"
                                         from: folderIcon.introScale
                                         to: (itemWidth / root.maxIconSizeInFolder) * root.iconScaleFactor
-                                        duration: 400
+                                        duration: 600
                                         easing.type: Easing.OutExpo
                                     }
                                     NumberAnimation {
                                         target: folderIcon
                                         property: "x"
                                         from: folderIcon.iconCenterX; to: iconItem.getItemX(index)
-                                        duration: 400
+                                        duration: 800
                                         easing.type: Easing.OutExpo
                                     }
                                     NumberAnimation {
                                         target: folderIcon
                                         property: "y"
                                         from: folderIcon.iconCenterY; to: iconItem.getItemY(index)
-                                        duration: 400
+                                        duration: 800
                                         easing.type: Easing.OutExpo
                                     }